Ablation method

ABSTRACT

A method of ablating a uterine fibroid using a particular trocar is disclosed. The trocar comprises a plurality of ablation stylets mounted for movement from within the trocar to positions extending from the trocar. The trocar is adjustable to assume a plurality of configurations, each of the configurations having the stylets extended to a different extent from the trocar. A region to be ablated is imaged. The region may correspond to all or a portion of a uterine fibroid. The size of the region to be ablated is noted. The size of the region to be ablated is compared to a matrix of known ablation regions, each of the known ablation regions being associated with one of the configurations of the particular trocar, and each of the known ablation regions being associated with a position of the trocar relative to the known ablation region. The region to be ablated is associated with a most nearly matching known ablation region by comparison of the region to be ablated to the known ablation regions. A trocar of the design of the particular trocar is inserted into the uterine fibroid at a position, with respect to the region to be ablated, which more closely matches the position of the particular trocar with respect to the known ablation region. The stylets are deployed from the trocar to an extent corresponding to the configuration associated with the most nearly matching known ablation region.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of U.S. patent applicationSer. No. 11/429,921, filed May 8, 2006, and entitled Anchored RFablation device for the destruction of tissue masses, which in turn is acontinuation in part of U.S. patent application Ser. No. 11/173,928,entitled Radio Frequency Ablation Device for the Destruction of TissueMasses filed on Jul. 1, 2005, the disclosures of which are incorporatedherein by reference.

TECHNICAL FIELD

The invention relates to apparatus and methods for uterine fibroidablation, and, in particular, to structures and methods for achievingfibroid tissue destruction in volumes with largely predictableorientations, dimensions and configurations.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

BACKGROUND OF THE INVENTION

Every year in the United States, approximately 230,000 women undergohysterectomies for removal of uterine fibroids. In addition, it has beenestimated that likely another six million women in the United Stateswith uterine fibroid symptoms prefer to suffer, rather than taking onthe risks and inconveniences associated with hysterectomy, the standardtreatment and a major surgery that always results in infertility. Thissituation is much the same in the other parts of the world where womenare in need of a safe alternative to hysterectomy.

Alternatives to hysterectomy such as uterine artery embolization (inwhich the blood supplies to the arteries that feed the fibroids are cutoff), and Myomectomy (which involves a surgical removal of the fibroid)do exist, but both these methods involve complicated surgical proceduresfollowed by a high rate of complications and a long recovery time.

In order to address these issues, an RF ablation probe that has beenused to treat tumors in the human liver by hyperthermia has beendemonstrated to substantially shrink or eliminate uterine fibroids.

One such device has been disclosed in U.S. Pat. No. 6,840,935 to Lee.According to the disclosure in that patent, an ablation apparatus withmultiple needles or deployable arms is inserted and positioned eitherproximate to or into a pelvic tumor, the location of which is furtherconfirmed by using a laparoscope and an ultrasound machine. Eitherelectromagnetic energy (and, potentially, other forms of energy) may bedelivered through the ablation apparatus to the pelvic tumor to inducehyperthermia and ablate the tumor.

A typical device for ablating pelvic tumors is sold by Rita MedicalSystems, Inc. This device consists of a plurality of resilient springypre-curved RF ablation antennae or stylets housed in a straight lumen.The stylets are ejected in a curved configuration defined by theirpreformed springy shapes as they exit a sharp-tipped catheter. Thedeployed antennae with their particular preformed shapes thus can definevariously shaped volumes by varying the configuration of the curveswhich are preformed into the various springy antennae.

SUMMARY OF THE INVENTION

In accordance with the invention, a method and apparatus are providedfor the ablation of uterine tissue. According to the present invention,a plurality of conductors are housed within the walls of a cannula, eachof which has a proximal end proximate to the proximal end of the cannulaand a distal end proximate to the distal end of the cannula. A pluralityof ablation stylets are coupled with each of these conductors such thatthe distal end of each conductor is connected to the proximal end of astylet. The conductors and their respective stylets are mounted withinthe cannula for axial movement and a trocar point defines the distal endof the cannula. A deflection surface can be defined by the metal elementdefining the trocar point between the trocar point and the proximal endof the cannula. In response to forward axial movement of the stylets, atleast some of them are deflected laterally and outwardly, with respectto the cannula axis in different directions along substantially straightpaths with the paths defining an ablation volume. The trocar point andthe stylets are provided with radio frequency energy, and together forman ablation zone.

In accordance with the invention a uterine fibroid is ablated using atrocar of known dimensional characteristics. The trocar comprises aplurality of ablation stylets mounted for movement from within thetrocar to positions extending from the trocar. The trocar is adjustableto assume a plurality of configurations, each of the configurationshaving the stylets extended to a different extent from the trocar. Aregion to be ablated is imaged. The region may correspond to all or aportion of a uterine fibroid. The size of the region to be ablated isnoted. The size of the region to be ablated is compared to a matrix ofknown ablation regions, each of the known ablation regions beingassociated with one of the configurations of the particular trocar ofknown dimensions, and each of the known ablation regions beingassociated with a position of the trocar relative to the known ablationregion. The region to be ablated is associated with a most nearlymatching known ablation region by comparison of the region to be ablatedto the known ablation regions. A trocar of the design of the particulartrocar is inserted into the uterine fibroid at a position, with respectto the region to be ablated, which more closely matches the position ofthe particular trocar with respect to the known ablation region. Thestylets are deployed from the trocar to an extent corresponding to theconfiguration associated with the most nearly matching known ablationregion.

BRIEF DESCRIPTION THE DRAWINGS

The operation of the invention will become apparent from the followingdescription taken in conjunction with the drawings, in which:

FIG. 1 a is a perspective view of a multiple antennae or stylet ablationinstrument 1 useful in practicing the inventive method;

FIG. 1 b is a detailed view of a multiple antennae or stylet ablationinstrument useful in practicing the inventive method;

FIG. 2 is a diagram illustrating an embodiment of the method asimplemented according to the present invention;

FIG. 3 illustrates another embodiment of the present invention in thecontext of achieving a larger ablation zone;

FIG. 4 is a diagram illustrating a method to achieve a still largerablation zone with the deployment of the stylets at a distance of 5 mminto a volume of uterine fibroid tissue;

FIG. 5 illustrates an embodiment of the present invention where thestylets are deployed to 10 mm resulting in a generally egg-shapedvolume;

FIG. 6 illustrates the inventive method in the context of achieving aneven larger ablation zone;

FIG. 7 illustrates the inventive method in the context of achievingstill an even larger ablation zone;

FIG. 8 illustrates the inventive method with the stylets deployed 25 mminto a volume of uterine fibroid tissue;

FIG. 9 illustrates the inventive method with the stylets deployed to 35mm into the uterine fibroid tissue;

FIG. 10 illustrates the inventive with the stylets at 45 mm; and

FIG. 11 illustrates the inventive method with the stylets deployed to 50mm, yielding a generally pear-shaped volume.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with the invention, it has been discovered that trocarpoint configuration, stylet length and ablation power level may be usedto create ablation zones of relatively predictable size and shape.

FIG. 1 a is a perspective view of an ablation instrument 1 with multipleantennae or stylets useful in practicing the inventive method. Ablationinstrument 1 with a head end comprising a trocar 1 a comprises a cannula2 which houses a plurality of stylets 3, and, optionally, a plurality ofanchors 4. A trocar point 5 is provided at the distal end of cannula 2.At least one conductor 6 is provided within cannula 2. Conductor 6 iselectrically coupled to stylets 3 and trocar point 4 and accordinglyprovides RF energy to stylets 3 and trocar point 5.

In accordance with the invention, stylets 3 and trocar point 5 areelectrically coupled to each other and electrically isolated from otherexposed portions of ablation instrument 1, such as cannula 2. Each ofthe stylets are made of thin wire-like tubular members and during theprocedure are initially housed entirely within the cannula 2. Stylets 3are deployed for ablation by being advanced in the forward directiontoward the distal end of ablation instrument 1 out from ablationinstrument 1 through openings 7. As stylets 3 are advanced throughopenings 7, they bear against deflection surfaces 8 and move into thepositions illustrated in FIG. 1. Deflection surfaces 8 are defined inthe metal body which defines trocar point 5 at the distal end of thecannula 2.

During the inventive method, trocar point 5 at the distal end of cannula2 is used to initially pierce the tissue of the fibroid tumor during useof the inventive ablation device 1. Optionally, a plurality of anchors9, also housed within ablation instrument 1, may be deployed rearwardlytoward the proximal end of ablation instrument 1. During deployment,anchors 4 are deflected by deflection surfaces 11 to move into thepositions illustrated in FIG. 1 a. After deployment anchors 4 act toprevent rear-ward movement of trocar point 5 during deployment ofstylets 3 out from ablation instrument 1.

Stylets 3 are deployed through the use of a slideably mounted operatormember 13 housed within cannula 2 and coupled to an operating handle atits proximal end. Anchors 4 may also be deployed through the use of aslideably mounted operator member (not illustrated) housed withincannula 2 and coupled to an operating handle at its proximal end. Thedistal end of operator member 13 is coupled to stylets 3 which may thusbe advanced an identical distance in unison.

In accordance with the invention, it has been found that by varying theextension of stylets 3 from the trocar point and by varying the powerapplied to stylets 3 and ablation point 5, the size and shape of theablation zone may be predictably controlled. For a trocar point ofparticular dimension, predetermined and relatively uniformly dimensionedand shaped ablation zones may be controllably created.

In accordance with the invention it is contemplated that three facetscut into a right circular cylindrical metal body with a diameter of 3.5mm define the shape and size of the trocar point. In accordance with theinvention, or a trocar with a diameter of approximately 3.5 mm a height12 of 8.2 mm has been found to yield excellent results. As shown in FIG.1 b, large facet 19 has a height 15 of approximately 6 mm. Large facet19 overlies the center of the trocar which defines a cylindrical passage17 (FIG. 1 a-b), through which stylet 3′ extends. Large facet 19 has anoblique length 15 a of about 7 mm.

Flat facets 21 have a height 23 of approximately 4.5 mm. Facet 19 isaccordingly somewhat larger in area as compared to the other two facets21. In accordance with a preferred embodiment, large flat facet 19 has alength at its widest girth of approximately 3 mm. Facets 21 areapproximately 2.6 mm at their widest girth, but are not symmetrical,each having a straight edge which, together with facet 19, forms thepoint of the trocar. As compared to facets 21, facet 19 extends about1.5 mm further (along the axis of cannula 2) from point 5 of the trocartoward the proximal end of ablation instrument 1. Facets 21 aresymmetrical with respect to each other. The angle between facet 19 andeach of the facets 21 is approximately 90°.

While the above-described trocar with the above dimensions as providedexcellent results, it is believed that similarly dimensioned pointedtrocars, of similar base diameter and length will provide good results.

In accordance with the invention, it is contemplated that the dimensionsof the trocar point may vary from the preferred embodiment detailedabove. More particularly, it is contemplated that, for the applicationof the device to fibrous growths (such as uterine fibroids), usingmaterials available today, the diameter of trocar point 5 may varybetween 1.5 and 7 mm, although with existing materials, a diameterbetween 2.75 and 4 mm is preferred and a diameter between 3.2 and 3.7 mmis most preferred. However, to the extent that stronger materials maycome to be known, smaller diameter trocars are more desirable, as theycause less trauma to the patient due to the wound created by theintroduction of the trocar and cannula into the body of the patient.Conversely, I larger dimensions may be tolerated in some applicationsthan the structure of the present invention can advantageously be usedwith a larger diameter cannula and trocar.

In accordance with a preferred embodiment, trocar point 5 is made ofstainless steel. Stylets 3 are made of tubular nickel titanium alloyhaving an outer diameter of approximately 0.4 mm. The transducer allowsthe surgeon to monitor the ablation procedure, and control the extent towhich RF energy raises the temperature of the surrounding tissue, andthus control the size of the ablation zone in which substantial orcomplete cellular necrosis is induced.

Example 1

As shown in FIG. 2, when trocar point 5, having the dimensions specifiedabove, is advanced into a volume of uterine fibroid tissue and rf energyapplied, an ablation zone 10 having a generally oval-shaped volume maybe produced. In accordance with this example of the invention, radiofrequency power at a frequency of 460 kilohertz is output into ablationinstrument 1, which is deployed without externally extending stylets asillustrated in FIG. 2. The radio frequency power output to trocar point5 is 15 watts. Radio frequency power output is produced for a period of15 seconds. The ablation zone 10 which is produced has an axial length12 of 1 cm and a diameter or width 14 of 0.8 cm. The tip of trocar 1 ais located approximately 0.1 cm from the distal edge of ablation volume10. It is noted that in this configuration, stylets 3 are whollycontained within cannula 2.

As illustrated in FIG. 2, it has accordingly been found that evenwithout extending the stylets, the trocar may be used to createrelatively small ablation zones. In accordance with the invention, atrocar having the particular configuration described above yieldedexcellent results.

Example 2

If a larger ablation zone is desired, in accordance with the invention,one may deploy trocar 1 a with trocar point 5, and having the dimensionsspecified above, into a volume of uterine fibroid tissue, to create anablation zone 20 having a generally global-shaped volume, as illustratedin FIG. 3. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output into ablation instrument 1 and inparticular trocar 1 a. The radio frequency power output to trocar 1 a is15 watts. Radio frequency power output is produced for a period of 60seconds. The ablation zone 20 which is produced has a length 22 of 1.5cm and a width 24 of 1.2 cm. The tip 5 of trocar 1 a is locatedapproximately 0.5 cm from the distal edge of ablation volume 10.Ablation zone 20 extends 1.2 centimeters behind trocar point 5. It isnoted that in this configuration, stylets 3 are still wholly containedwithin cannula 2.

Example 3

In accordance with the invention, it is also possible to maintain thetemperature surrounding ablation stylets 3 for a period of time, asopposed to applying a fixed amount of power to trocar 1 a. For example,if a still a larger ablation zone is desired as compared to the ablationzone created in Example 2, in accordance with the invention, one maydeploy trocar 1 a, having the dimensions specified above, into a volumeof uterine fibroid tissue, to create an ablation zone 30, having agenerally egg-shaped volume, as illustrated in FIG. 4. In accordancewith the invention, radio frequency power at a frequency of 460 kHz isoutput into ablation instrument 1. Stylets 3 are deployed a distance of5 mm from the surface of trocar 1 a, thus resulting in exposing 5 mm oftheir length to the uterine fibroid tissue to be ablated.

The radio frequency power output to stylets 3 and trocar 1 a may bevaried in analog fashion to maintain a temperature of 100° centigradefor a period of 60 seconds. Feedback from the temperature transducerscontained within stylets 3 is used to adjust the power output of the RFgenerator to achieve the desired temperature.

Alternatively, the duty cycle of, for example, a 15 watt radio frequencyoutput coupled to trocar 1 a may be varied, for example by turning theoutput on to begin the heating cycle and reach the desired temperature,shutting it off when a desired temperature of 100° C. is achieved, andturning it on again when the temperature drops below 99.5° C.

The ablation zone 30 which is produced has a length 32 of 2 cm and awidth 34 of 1.6 cm. The tip of stylet 3′ is located at a distance 36approximately 0.8 cm from the distal edge of ablation volume 30.Ablation zone 30 extends 1.2 centimeters behind trocar point 5.

It is further noted that in accordance with the present invention,suitable, but smaller ablation zones may be obtained by maintainingtemperatures at various points within a range of, for example, 90 to100° C. In addition, it may be desirable to use higher temperatures orhigher powers toward the end of the ablation procedure, depending uponwhether there is temperature maintenance as in this example or powermaintenance as in Examples 1 and 2.

Example 4

If still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 40, having a generally egg-shaped volume, as illustrated in FIG. 5.In accordance with the invention, radio frequency power at a frequencyof 460 kHz is output into trocar 1 a. Stylets 3 are deployed a distanceof 10 mm from the surface of trocar 1 a on ablation device 1, thusresulting in exposing 10 mm of their length to the uterine fibroidtissue to be ablated. The temperature of the tissue surrounding stylets3 and trocar 1 a maintained at about 100° using either of the methodsdetailed above. Temperature is maintained for a period of 30 seconds.The ablation zone 40 which is produced has a length 42 of 25 mm and awidth 44 of 23 mm. The tip of stylet 3′ is located at a distance 46approximately 11 mm from the distal edge of ablation volume 40.Similarly, ablation zone 40 extends about 14 mm behind trocar point 5.

Example 5

If still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 50, having a generally pear-shaped volume, as illustrated in FIG.6. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output into ablation instrument 1. Stylets 3 aredeployed a distance of 15 mm from the surface of ablation device 1, thusresulting in exposing 15 mm of their length to the uterine fibroidtissue to be ablated. The temperature of the tissue surrounding stylets3 and trocar 1 a is maintained at about 100° using either of the methodsdetailed above. Temperature is maintained for a period of 120 seconds.The ablation zone 50 which is produced has a length 52 of 30 mm and awidth 54 of 26 mm. The tip of stylet 3′ is located at a distance 56approximately 11 mm from the distal edge of ablation volume 50.Similarly, ablation zone 50 extends about 12 mm behind trocar point 5.

Example 6

If an even larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a into a fibroid to be ablated.Trocar 1 a has the dimensions specified above and is positioned in avolume of uterine fibroid tissue to be ablated. Trocar 1 a may be drivenwith RF energy to create an ablation zone 60, having a generallypear-shaped volume, as illustrated in FIG. 7. In accordance with theinvention, radio frequency power at a frequency of 460 kHz is outputinto trocar 1 a on ablation instrument 1. Stylets 3 are deployed adistance of 20 mm from the surface of ablation device 1, thus resultingin exposing 20 mm of their length to the uterine fibroid tissue to beablated. The temperature of the tissue surrounding stylets 3 and trocar1 a is maintained at about 100° using either of the methods detailedabove. Temperature is maintained for a period of 180 seconds. Theablation zone 60 which is produced has a length 62 of 36 mm and a width64 of 31 mm. The tip of stylet 3′ is located at a distance 66approximately 11 mm from the distal edge of ablation volume 60 thusproduced. Ablation zone 60 extends about 12 mm behind trocar point 5.

Example 7

If still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 70, having a generally pear-shaped volume, as illustrated in FIG.8. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output into trocar 1 a on ablation instrument 1.Stylets 3 are deployed a distance of 25 mm from the surface of trocar 1a, thus resulting in exposing 25 mm of their length to the uterinefibroid tissue to be ablated. The temperature of the tissue surroundingstylets 3 and trocar 1 a is maintained at about 100° using either of themethods detailed above. Temperature is maintained for a period of 240seconds. The ablation zone 70 which is produced has a length 72 of 38 mmand a width 74 of 31 mm. The tip of stylet 3′ is located at a distance76 approximately 10 mm from the distal edge of ablation volume 70.Similarly, ablation zone 70 extends about 12 mm behind trocar point 5.

Example 8

If still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 80, having a generally pear-shaped volume, as illustrated in FIG.9. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output trocar 1 a. Stylets 3 are deployed adistance of 35 mm from the surface of trocar 1 a, thus resulting inexposing 35 mm of their length to the uterine fibroid tissue to beablated. The temperature of the tissue surrounding stylets 3 and trocar1 a maintained at about 100° using either of the methods detailed above.Temperature is maintained for a period of 420 seconds. The ablation zone80 which is produced has a length 82 of 49 mm and a width 84 of 41 mm.The tip of stylet 3′ is located at a distance 86 approximately 12 mmfrom the distal edge of ablation volume 80. Similarly, ablation zone 80extends about 12 mm. behind trocar point 5.

Example 9

If yet a still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 90, having a generally pear-shaped volume, as illustrated in FIG.10. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output to trocar 1 a. Stylets 3 are deployed adistance of 45 mm from the surface of trocar 1 a, thus resulting inexposing 45 mm of their length to the uterine fibroid tissue to beablated. The temperature of the tissue surrounding stylets 3 and trocar1 a maintained at about 100° using either of the methods detailed above.Temperature is maintained for a period of 480 seconds. The ablation zone90 which is produced has a length 92 of 59 mm and a width 94 of 46 mm.The tip of stylet 3′ is located at a distance 96 approximately 11 mmfrom the distal edge of ablation volume 90. Ablation zone 90 extends 11mm behind trocar point 5.

Example 10

If still a larger ablation zone is desired, in accordance with theinvention, one may deploy trocar 1 a, having the dimensions specifiedabove, into a volume of uterine fibroid tissue, to create an ablationzone 100, having a generally pear-shaped volume, as illustrated in FIG.11. In accordance with the invention, radio frequency power at afrequency of 460 kHz is output to trocar 1 a. Stylets 3 are deployed adistance of 50 mm from the surface of ablation device 1, thus resultingin exposing 50 mm of their length to the uterine fibroid tissue to beablated. The temperature of the tissue surrounding stylets 3 and trocar1 a is maintained at about 100° using either of the methods detailedabove. Temperature is maintained for a period of 720 seconds. Theablation zone 100 which is produced has a length 102 of 67 mm and awidth 104 of 59 mm. The tip of stylet 3′ is located at a distance 96approximately 14 mm from the distal edge of ablation volume 90.Similarly, ablation zone 90 extends about 11 mm behind trocar point 5.

In accordance with the invention, in the power mode typified by theembodiments of FIGS. 2 and 3, the RF generator delivers substantiallyconstant RF power at 460 kHz to all electrodes and the mandrel tip.

In accordance with a preferred embodiment of the invention, athermocouple is provided at the distal end of each stylet electrode.While all the strategies may be used, in a temperature-controlledablation, such as Example 3, the system may use the average temperatureof the seven thermocouples to control the power output. Alternatively,high and/or low readings may be removed from the calculation.

Optionally, one may employ a power control algorithm which operatesdifferently while it is ramping up to a target temperature, as comparedto its operation when it is at or near the target temperature. Inaccordance with a preferred embodiment of the invention, in rampingmode, a ramping mode power control algorithm applies the full power ofthe system, reduced by an amount, if any, which causes the system toimplement a maximum temperature increase rate of 2° C./second. Inaccordance with the invention, this ramp rate may be reduced as averagetemperature measured by the temperature transducers in the probe'sablation stylets approach the target temperature.

When the probe average temperature is below, and within, for example,0.5° C. of the target temperature, the power control algorithm switchesto target power control mode where power is moderated and adjusted tomaintain the desired temperature. Target power control delivers power inproportion to the small differences between the thermocouple average andthe target temperature.

After the algorithm has switched from ramping to target power controlmode, the system may be set to never switch back to ramping mode untilthe RF power is turned off. That means once target temperature isachieved the amount of RF Power delivered is only to maintain targettemperature, in the embodiment of Example 3 and other temperaturecontrolled procedures.

As alluded to above, manual (or power) control mode simply delivers theamount of power to the electrode array and tip that has been set as thetarget power.

In both temperature and manual modes, the amount of ablation time iscontrolled by a foot pedal that is used to start and stop the RFdelivery.

While illustrative embodiments of the invention have been described, itis noted that various modifications will be apparent to those ofordinary skill in the art in view of the above description and drawings.Such modifications are within the scope of the invention which islimited and defined only by the following claims.

1. A method of ablating a uterine fibroid using a particular trocar,said trocar comprising a plurality of ablation stylets mounted formovement from within said trocar to positions extending from saidtrocar, said trocar being adjustable to assume a plurality ofconfigurations, each of said configurations having said stylets extendedto a different extent from said trocar, comprising: (a) imaging a regionto be ablated, said region corresponding to all or a portion of auterine fibroid; (b) noting the size of said region to be ablated; (c)comparing the size of said region to be ablated to a matrix of knownablation regions, each of said known ablation regions being associatedwith one of said configurations of said particular trocar, each of saidknown ablation regions being associated with a position of said trocarrelative to said known ablation region; (d) associating said region tobe ablated with a most nearly matching known ablation region bycomparison of said region could be ablated to said known ablationregions; (e) inserting a trocar of the design of said particular trocarinto said uterine fibroid at a position, with respect to said region tobe ablated, which more closely matches the position of said particulartrocar with respect to said known ablation region; and (f) deployingsaid stylets from said trocar to an extent corresponding to saidconfiguration associated with said most nearly matching known ablationregion.
 2. A method for ablating a uterine fibroid as in claim 1,further comprising: (g) insufflating the abdominal cavity of the patientto create an air pocket adjacent to said uterus and within the abdominalcavity; and (h) placing a laparoscope in said air pocket in a positionto optically image said uterus.
 3. A method for ablating a uterinefibroid as in claim 2, wherein said known ablation region is associatedwith a particular length for stylet deployment and an associatedablation time, and wherein said stylets are deployed to said particularlength, and further comprising: (i) applying RF power to said styletsand said trocar for said associated ablation time; and (j) withdrawingsaid trocar.
 4. A method as in claim 3, wherein cautery RF power it isapplied to said trocar chewing withdrawal of said trocar.
 5. An ablationprocedure as in claim 3, further comprising: (k) noting the orientationof said region to be ablated.
 6. An ablation procedure as in claim 3,wherein temperature of at least one stylet is measured, and wherein RFpower is maintained during the procedure at a level which results insaid temperature having an average value in the range between 90°centigrade and 100° centigrade during the ablation procedure.
 7. Anablation procedure as in claim 3, wherein said stylets are deployedbetween 2.5 and 7.5 mm, wherein RF power is applied for between 30seconds and 90 seconds, wherein temperature of at least one stylet ismeasured, and wherein RF power is maintained during the procedure at alevel which results in said temperature having an average value in therange between 80° centigrade and 110° centigrade during the ablationprocedure.
 8. An ablation procedure as in claim 3, wherein said styletsare deployed between 7.5 and 12.5 mm, wherein RF power is applied forbetween 15 seconds and 60 seconds, wherein temperature of at least onestylet is measured, and wherein RF power is maintained during theprocedure at a level which results in said temperature having an averagevalue in the range between 80° centigrade and 110° centigrade during theablation procedure.
 9. An ablation procedure as in claim 3, wherein saidstylets are deployed between 12.5 and 17.5 mm, wherein RF power isapplied for between 60 seconds and 150 seconds, wherein temperature ofat least one stylet is measured, and wherein RF power is maintainedduring the procedure at a level which results in said temperature havingan average value in the range between 80° centigrade and 110° centigradeduring the ablation procedure.
 10. An ablation procedure as in claim 3,wherein said stylets are deployed between 17.5 and 22.5 mm, wherein RFpower is applied for between 150 seconds and 210 seconds, whereintemperature of at least one stylet is measured, and wherein RF power ismaintained during the procedure at a level which results in saidtemperature having an average value in the range between 80° centigradeand 110° centigrade during the ablation procedure.
 11. An ablationprocedure as in claim 3, wherein said stylets are deployed between 22.5and 30 mm, wherein RF power is applied for between 210 seconds and 330seconds, wherein temperature of at least one stylet is measured, andwherein RF power is maintained during the procedure at a level whichresults in said temperature having an average value in the range between80° centigrade and 110° centigrade during the ablation procedure.
 12. Anablation procedure as in claim 3, wherein said stylets are deployedbetween 30 and 40 mm, wherein RF power is applied for between 330seconds and 450 seconds, wherein temperature of at least one stylet ismeasured, and wherein RF power is maintained during the procedure at alevel which results in said temperature having an average value in therange between 85° centigrade and 105° centigrade during the ablationprocedure.
 13. An ablation procedure as in claim 3, wherein said styletsare deployed between 40 and 47.5 mm, wherein RF power is applied forbetween 450 seconds and 600 seconds, wherein temperature of at least onestylet is measured, and wherein RF power is maintained during theprocedure at a level which results in said temperature having an averagevalue in the range between 85° centigrade and 105° centigrade during theablation procedure.
 14. An ablation procedure as in claim 3, whereinsaid stylets are deployed between 47.5 and 60 mm, wherein RF power isapplied for between 600 seconds and 900 seconds, wherein temperature ofat least one stylet is measured, and wherein RF power is maintainedduring the procedure at a level which results in said temperature havingan average value in the range between 85° centigrade and 105° centigradeduring the ablation procedure.
 15. A method of ablating a uterinefibroid using a particular trocar, said trocar comprising a plurality ofablation stylets mounted for movement from within said trocar topositions extending from said trocar, said trocar being adjustable toassume a plurality of configurations, each of said configurations havingsaid stylets extended to a different extent from said trocar,comprising: (a) imaging a region to be ablated, said regioncorresponding to all or a portion of a uterine fibroid; (b) noting thesize of said region to be ablated; (c) comparing the size of said regionto be ablated to a matrix of known ablation regions, each of said knownablation regions being associated with one of said configurations ofsaid particular trocar, each of said known ablation regions beingassociated with a position of said trocar relative to said knownablation region; (d) associating said region to be ablated with a mostnearly matching known ablation region by comparison of said region couldbe ablated to said known ablation regions; (e) inserting a trocar of thedesign of said particular trocar into said uterine fibroid at aposition, with respect to said region to be ablated, which more closelymatches the position of said particular trocar with respect to saidknown ablation region; and (f) applying a substantially fixed rf powerto said trocar for a fixed period of time.